1. Field of the Invention
The present invention relates to novel alkylenediamine derivatives. The alkylenediamine derivatives of the invention are favorably employable as glutamate blockers.
2. Description of Prior Art
It is generally accepted that glutamate serves as an excitatory transmitter in the Crustacea. Further, it is also considered that glutamate is a potent candidate of the excipitory transmitter even in the central nervous system of mammals.
There is known .gamma.-methylester of glutamic acid as a glutamate blocker which is effective to inhibit the above-mentioned functions of glutamate. However, the glutamate blocking function of the .gamma.-methylester of glutamic acid is observed only when it is employed at high concentrations such as 10.sup.-2 m to 10.sup.-3 M. Accordingly, the .gamma.-methylester is not satisfactory from the viewpoint of practical employment as the glutamate blocker.
It is further reported that Diltiazem and Caroberine also show inhibition against the functions of glutamate :see "Seitai no Kagaku" in Japanese Language, 30(2): 8291, 1979. However, the inhibitory function of these compounds is weak, as compared with other blockers employed in other transmission systems, such as anticholinergic agents against acetylcoline and antihistamines against histamine. For instance, at dose of 2.times.10.sup.-4 Diltiazem and Caroberine both are effective only such low level as to inhibit approx. 30% of depolarization induced in the case of applying glutamic acid (1.times.10.sup.-4 M) to the opener muscle of the first walking leg of the crayfish. Further, the action provided by these known compounds is not selective.
Furthermore, it has been reported that aminoalcohol derivatives such as 5-methyl-1-phenyl-2-(3-piperidinopropylamino)hexan-1-ol show the glutamate blocking function. However, the glutamate blocking functions of these amino-alcohol derivatives are not sufficiently high if the administration is made at a low level.